Interposer and probe card having the same

ABSTRACT

An interposer may include a first base, at least one first signal line in the first base, and at least one first ground line in the first base, wherein the ground line surrounds the at least one first signal line. The at least one first signal line and the at least one first ground line may be exposed through an upper surface of the first base. The at least one first signal line may be configured to conduct a test current through the first base. An interposer may also include a second base below the first base and may include a printed circuit board between the first base and the second base. A probe card may include a multilayer substrate having at least one contact needle, a coaxial board having at least one coaxial signal cable and the above described interposer between the multilayer substrate and the coaxial board.

PRIORITY STATEMENT

This application claims priority under 35 U.S.C. §119 to Korean PatentApplication No. 2007-104922, filed on Oct. 18, 2007, in the KoreanIntellectual Property Office (KIPO), the entire contents of which areherein incorporated by reference.

BACKGROUND

1. Field

Example embodiments relate to an interposer and a probe card having thesame. More particularly, example embodiments relate to an interposerconnected between a coaxial board and a multilayer substrate, and aprobe card having the interposer.

2. Description of the Related Art

Various semiconductor fabricating processes may be performed on a waferto form a plurality of semiconductor structures. Electricalcharacteristics of the semiconductor structures may be tested using aprobe apparatus.

The probe apparatus may include a tester for generating a test current,a probe card making contact with the semiconductor structures to supplythe test current to the semiconductor structures, and a performanceboard arranged between the tester and the probe card to transmit thetest current to the probe card.

The conventional probe card may include a multilayer substrate havingneedles that contact an object, a coaxial board having a coaxial cablefor supplying the test current from the performance board to theneedles, and an interposer interposed between the coaxial board and themultilayer substrate to serve as a medium for transmitting the testcurrent to the needles.

The conventional interposer may include a resilient base, signal linesbuilt into the base, and ground lines built into the base. The signallines and the ground lines may be alternately arranged. Generally,interposers do not include structures to prevent crosstalk betweensignal lines.

Crosstalk between the signal lines may become relatively excessive inconventional interposers. In particular, crosstalk may become relativelyexcessive in proportion to a rapid transmission speed of the testcurrent and may be caused by a narrow interval between patterns on asemiconductor substrate. The crosstalk may cause loss of the testcurrent, so that test reliability of the semiconductor structures may besignificantly reduced.

SUMMARY

Example embodiments of the present invention provide an interposer thatmay be capable of suppressing a crosstalk between signal lines.

An interposer according to example embodiments may include a first base,at least one first signal line in the first base, and at least one firstground line in the first base, wherein the ground line surrounds the atleast one first signal line. In accordance with example embodiments, theat least one first signal line and the at least one first ground linemay be exposed through an upper surface of the first base. In accordancewith example embodiments, the at least one first signal line and may beconfigured to conduct a test current through the first base. Inaccordance with example embodiments a probe card may include the abovedescribed interposer.

An interposer, according to example embodiments, may include the firstbase as described above and may also include a second base, and aprinted circuit board between the first base and the second base. Inaccordance with example embodiments at least one second signal linesurrounded by at least one second ground line may be provided in the inthe second base. The at least one second signal line and the at leastone second ground line may be exposed through a lower surface of thesecond base and the at least one second signal line may be configured toconduct a test current. The printed circuit board may include at leastone signal plug to electrically connect the at least one first signalline to the at least one second signal line and may also include atleast one ground plug to electrically connect the at least one firstground line to the at least one second ground line. In accordance withexample embodiments a probe card may include the above describedinterposer.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of example embodiments willbecome more apparent by describing in detail example embodiments withreference to the accompanying drawings, in which:

FIG. 1 is a perspective view illustrating an interposer in accordancewith example embodiments;

FIG. 2 is a side view illustrating the interposer in FIG. 1;

FIG. 3 is an enlarged perspective view of a portion III in FIG. 1;

FIG. 4 is a cross-sectional view taken along a line IV-IV′ in FIG. 3;

FIG. 5 is a perspective view illustrating an interposer in accordancewith example embodiments;

FIG. 6 is a side view illustrating the interposer in FIG. 5;

FIG. 7 is a cross-sectional view taken along a line VI-VI′ in FIG. 5;

FIG. 8 is a plan view illustrating a printed circuit board of theinterposer in FIG. 5;

FIG. 9 is a side view illustrating a probe card in accordance withexample embodiments; and

FIG. 10 is a side view illustrating a probe card in accordance withexample embodiments.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

Example embodiments are described more fully hereinafter with referenceto the accompanying drawings, in which example embodiments are shown.Example embodiments may, however, be embodied in many different formsand should not be construed as limited to example embodiments set forthherein. Rather, example embodiments are provided so that this disclosurewill be thorough and complete, and will fully convey the scope ofexample embodiments to those skilled in the art. In the drawings, thesizes and relative sizes of layers and regions may be exaggerated forclarity.

It will be understood that when an element or layer is referred to asbeing “on,” “connected to” or “coupled to” another element or layer, itcan be directly on, connected or coupled to the other element or layeror intervening elements or layers that may be present. In contrast, whenan element is referred to as being “directly on,” “directly connectedto” or “directly coupled to” another element or layer, there are nointervening elements or layers present. Like numerals refer to likeelements throughout. As used herein, the term “and/or” includes any andall combinations of one or more of the associated listed items.

It will be understood that, although the terms first, second, third etc.may be used herein to describe various elements, components, regions,layers and/or sections, these elements, components, regions, layersand/or sections should not be limited by these terms. These terms areonly used to distinguish one element, component, region, layer orsection from another region, layer or section. Thus, a first element,component, region, layer or section discussed below could be termed asecond element, component, region, layer or section without departingfrom the teachings of example embodiments.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the exemplary term “below” can encompass both anorientation of above and below. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting of exampleembodiments. As used herein, the singular forms “a,” “an,” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“comprises” and/or “comprising,” when used in this specification,specify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof.

Example embodiments are described herein with reference tocross-sectional illustrations that are schematic illustrations ofidealized example embodiments (and intermediate structures) of exampleembodiments. As such, variations from the shapes of the illustrations asa result, for example, of manufacturing techniques and/or tolerances,are to be expected. Thus, example embodiments should not be construed aslimited to the particular shapes of regions illustrated herein but areto include deviations in shapes that result, for example, frommanufacturing. For example, an implanted region illustrated as arectangle will, typically, have rounded or curved features and/or agradient of implant concentration at its edges rather than a binarychange from implanted to non-implanted region. Likewise, a buried regionformed by implantation may result in some implantation in the regionbetween the buried region and the surface through which the implantationtakes place. Thus, the regions illustrated in the figures are schematicin nature and their shapes are not intended to illustrate the actualshape of a region of a device and are not intended to limit the scope ofexample embodiments.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art andwill not be interpreted in an idealized or overly formal sense unlessexpressly so defined herein.

Hereinafter, example embodiments will be explained in detail withreference to the accompanying drawings.

FIG. 1 is a perspective view illustrating an interposer in accordancewith some example embodiments. FIG. 2 is a side view illustrating theinterposer in FIG. 1. FIG. 3 is an enlarged perspective view of aportion III in FIG. 1. FIG. 4 is a cross-sectional view taken along aline IV-IV′ in FIG. 3.

Referring to FIGS. 1 to 4, an interposer 100 according to exampleembodiments may include a base 110, a plurality of signal lines 120, anda plurality of ground lines 130. The base 110 may have a rectangularplate shape. In example embodiments, the base 110 may include aresilient material such as a rubber. Further, the base 110 may have aplurality of first via holes 113. Each of the first via holes 113 mayhave a circular shape. Further, the first via holes 113 may be arrangedlengthwise and breadthwise directions by substantially the sameinterval.

Further, the base 110 may have a plurality of second via holes 115. Eachof the second via holes 115 may have an annular shape. Each of thesecond via holes 115 may surround each of the first via holes 113. Thus,each of the second via holes 115 may have a diameter longer than that ofeach of the first via holes 113. Further, the first via holes 113 andthe second via holes 115 may be arranged in a concentric circle. Here,because the first via holes 113 may be arranged in the lengthwise andbreadthwise directions by substantially the same interval, the secondvia holes 115 may also be arranged in the lengthwise and breadthwisedirections by substantially the same interval.

Additionally, the base may include first protrusions 112 and secondprotrusions 114 protruded from an upper surface of the base 110, andthird protrusions 116 and fourth protrusions 118 protruded from a lowersurface of the base 110.

The first protrusions 112 and the third protrusions 116 may define thefirst via holes 113. For example, the first via holes 113 may be formedin the first protrusions 112. In example embodiments, the firstprotrusions 112 may have an annular shape having a diameter longer thanthat of the first via holes 113. Here, the third protrusions 116 mayhave a shape and an arrangement pattern substantially the same as thoseof the first protrusions 112. Therefore, any further illustrations withrespect to the third protrusions 116 are omitted herein for brevity.

The second protrusions 114 and the fourth protrusions 118 may define thesecond via holes 115. In example embodiments, the second protrusions 114may have an annular shape having a diameter longer than that of thesecond via holes 115. Accordingly, a space formed between an outersurface of the first protrusion 112 and an inner surface of the secondprotrusion 114 may correspond to the second via hole 115. Here, thefourth protrusions 118 may have a shape and an arrangement patternsubstantially the same as those of the second protrusions 114.Therefore, any further illustrations with respect to the fourthprotrusions 118 are omitted herein for brevity.

Further, because the first via holes 113 and the second via holes 115may be arranged in the concentric circle, the first protrusions 112 andthe second protrusion 114 may also be arranged in a concentric circle.

Furthermore, since the first via holes 113 and the second via holes 115may be arranged in the lengthwise and breadthwise directions bysubstantially the same interval, the first protrusions 112 and thesecond protrusions 114 may also be arranged in the lengthwise andbreadthwise directions by substantially the same interval.

The signal lines 120 may be formed in the first via holes 113. Inexample embodiments, the first via holes 113 may be filled withconductive particles to form the solid signal lines 120 having acylindrical shape in the base 110. Examples of the conductive particlesmay include gold, silver, copper and the like.

The ground lines 130 may be formed in the second via holes 115. Inexample embodiments, the second via holes 115 may be filled withconductive particles to form the hollow ground lines 130 having acylindrical shape in the base 110. Examples of the conductive particlesused for the ground lines 130 may be substantially the same as thoseused for the signal lines 120.

According to example embodiments, each of the ground lines 130 maysurround each of the ground signal lines 120. Thus, the ground lines 130may block a crosstalk between the signal lines 120. As a result, a lossof a test current flowing through the signal lines may be suppressed.

FIG. 5 is a perspective view illustrating an interposer in accordancewith example embodiments. FIG. 6 is a side view illustrating theinterposer in FIG. 5. FIG. 7 is a cross-sectional view taken along aline VI-VI′ in FIG. 5. FIG. 8 is a plan view illustrating a printedcircuit board of the interposer in FIG. 5.

Referring to FIGS. 5 to 8, an interposer 200 according to exampleembodiments may include a first interposing member 210, a secondinterposing member 220 and a printed circuit board (PCB) 230.

Here, the first interposing member 210 may have a structuresubstantially the same as an upper structure of the interposer 100 inFIG. 1. Further, the second interposing member 220 may have a structuresubstantially the same as a lower structure of the interposer 100 inFIG. 1.

The first interposing member 210 may include a first base 212, aplurality of first signal lines 214 built into the first base 212, and aplurality of first ground lines 216 built into the first base 212 tosurround the first signal lines 214, respectively.

The second interposing member 220 may include a second base 222, aplurality of second signal lines 224 built into the second base 222, anda plurality of second ground lines 226 built into the second base 222 tosurround the second signal lines 224, respectively.

The PCB 230 may be arranged between the first interposing member 210 andthe second interposing member 220. Here, the first interposing member210 and the second interposing member 220 may include a resilientmaterial, for example, rubber. The PCB 230 may be interposed between thefirst interposing member 210 and the second interposing member 220. Thefirst interposing member 210 may be attached to an upper surface of thePCB 230. The second interposing member 220 may be attached to a lowersurface of the PCB 230.

The PCB 230 may have a plurality of first via holes 236 and a pluralityof second via holes 238. In example embodiments, four second via holes238 may be arranged at a periphery of one first via hole 236. Aplurality of signal plugs 232 may be formed in the first via holes 236.A plurality of ground plugs 234 may be formed in the second via holes238.

The signal plugs 232 may function as to electrically connect the firstsignal lines 214 with the second signal lines 224. For example, thefirst signal lines 214 may make contact with upper ends of the signalplugs 232. The second signal lines 224 may make contact with lower endsof the signal plugs 232. Therefore, the first signal line 214, thesignal plug 232 and the second signal line 224 may have a coaxialvertical axis.

The ground plugs 234 may function as to electrically connect the firstground lines 216 with the second ground lines 226. For example, thefirst ground lines 216 may make contact with upper ends of the groundplugs 234. The second ground lines 226 may make contact with lower endsof the ground plugs 234. Therefore, the first ground line 216, theground plug 234 and the second ground line 226 may have a coaxialvertical axis.

FIG. 9 is a side view illustrating a probe card in accordance withexample embodiments. Referring to FIG. 9, a probe card 300 according toexample embodiments may include a multilayer substrate 310, a coaxialboard 330, and an interposer 100 between the multilayer substrate 310and the coaxial board 330.

The interposer 100 may include elements substantially the same as thoseof the interposer described in FIG. 1. Thus, the same reference numeralsmay refer to the same elements and any further illustrations withrespect to the same elements are omitted herein for brevity.

The multilayer substrate 310 may be positioned over an object, e.g., asemiconductor substrate. The interposer 100 may be placed on themultilayer substrate 310. In example embodiments, the multilayersubstrate 310 may have a structure where a plurality of insulatingsubstrates may be stacked. An example of the insulating substrate mayinclude a ceramic. Circuit patterns (not shown) may be built into themultilayer substrate 310. The circuit patterns may be exposed through anupper surface and a lower surface of the multilayer substrate 310. Thecircuit patterns may be electrically connected to the signal lines 120of the interposer 100 (see FIG. 1). A plurality of needles 320 may makecontact with the object and may be arranged on the lower surface of themultilayer substrate 310. The needles 320 may be electrically connectedto the circuit patterns. Therefore, the needles 320 may be electricallyconnected to the signal lines 120 of the interposer 100 via the circuitpatterns.

The coaxial board 330 may be located on the interposer 100. The coaxialboard 330 may include coaxial signal cables 332 and coaxial groundcables 334. The coaxial signal cables 332 may be electrically connectedto the signal lines 120 of the interposer 100. The coaxial ground cables334 may be electrically connected to the ground lines 130 of theinterposer 100.

A performance board 340 may be arranged over the coaxial board 330. Theperformance board 340 may transmit a test current generated from atester (not shown) to the coaxial signal cables 332.

According to example embodiments, the interposer including the signallines surrounded with the ground lines may be employed in the probecard. Thus, test reliability using the probe card may be significantlyimproved.

FIG. 10 is a side view illustrating a probe card in accordance withexample embodiments. Referring to FIG. 10, a probe card 300a accordingto example embodiments may include a multilayer substrate 310, a coaxialboard 330, and an interposer 200 between the multilayer substrate 310and the coaxial board 330.

The interposer 200 may include elements substantially the same as thoseof the interposer in FIG. 5. Thus, the same reference numerals may referto the same elements and any further illustrations with respect to thesame elements are omitted herein for brevity.

Further, the multilayer substrate 310 and the coaxial board 330 may besubstantially the same as those in FIG. 9. Thus, the same referencenumerals may refer to the same elements and any further illustrationswith respect to the same elements are omitted herein for brevity.

The first interposing member 210 (see FIG. 6) of the interposer 200 maybe placed under the coaxial board 330. The first signal lines 214 (seeFIG. 6) of the first interposing member 210 may be electricallyconnected to the coaxial signal cables 332 of the coaxial board 330. Thefirst ground lines 216 of the first interposing member 210 may beelectrically connected to the coaxial ground cables 334 of the coaxialboard 330.

The second interposing member 220 (see FIG. 6) of the interposer 200 maybe placed over the multilayer substrate 310. The second signal lines 224(see FIG. 7) of the second interposing member 220 may be electricallyconnected to the circuit patterns of the multilayer substrate 310.

According to example embodiments, each of the ground lines may surroundeach of the signal lines. Thus, a crosstalk between the signal lines maybe suppressed. As a result, a loss of the test current flowing throughthe signal lines may be suppressed, so that test reliability using theprobe card may be significantly improved.

The foregoing is illustrative of example embodiments and is not to beconstrued as limiting thereof. Although example embodiments have beendescribed, those skilled in the art will readily appreciate that manymodifications are possible in example embodiments without materiallydeparting from the novel teachings and advantages of exampleembodiments. Accordingly, all such modifications are intended to beincluded within the scope of example embodiments as defined in theclaims. In the claims, means-plus-function clauses are intended to coverthe structures described herein as performing the recited function andnot only structural equivalents but also equivalent structures.Therefore, it is to be understood that the foregoing is illustrative ofexample embodiments and is not to be construed as limited to exampleembodiments disclosed, and that modifications to example embodiments areintended to be included within the scope of the appended claims. Exampleembodiments are defined by the following claims, with equivalents of theclaims to be included therein.

1. An interposer comprising: a first base; at least one first signalline in the first base, wherein the at least one first signal line isexposed through an upper surface of the first base and the at least onefirst signal line is configured to conduct a test current through thefirst base; and at least one first ground line in the first base, the atleast one first ground line surrounding the at least one first signalline, wherein the at least one first ground line is exposed through theupper surface.
 2. The interposer of claim 1, wherein the at least onefirst ground line and the at least one first signal line are exposedthrough a lower surface of the first base.
 3. The interposer of claim 2,wherein the base comprises: at least one first via hole through thefirst base configured to receive that the at least one first signalline; and at least one second via hole through the first base, the atleast one second via hole surrounding the at least one first via holeand configured to receive the at least one first ground line.
 4. Theinterposer of claim 3, wherein the at least one first via hole has acircular shape and the at least one second via hole has an annularshape.
 5. The interposer of claim 3, wherein the first base furthercomprises: at least one first protrusion protruding from the uppersurface and the lower surface of the first base to define the at leastone first via hole; and at least one second protrusion protruding fromthe upper surface and the lower surface of the first base to define theat least one second via hole.
 6. The interposer of claim 2, wherein thefirst base comprises a resilient material.
 7. The interposer of claim 2,wherein the at least one first signal line and the at least one firstground line are in a concentric circle.
 8. The interposer of claim 2,wherein the at least one first ground line is a first plurality ofground lines spaced apart from one another by substantially the sameinterval and the at least one first signal line is a first plurality ofsignal lines spaced apart from one another by substantially the sameinterval, wherein each of the ground lines among the first plurality offirst ground lines surrounds a corresponding signal line among the firstplurality of signal lines.
 9. The interposer of claim 2, wherein the atleast one first signal line and the at least one first ground lineinclude conductive particles.
 10. The interposer of claim 9, wherein theconductive particles comprise gold, silver or copper.
 11. The interposerof claim 1, further comprising: a second base below the first base; atleast one second signal line in the second base, wherein the at leastone second signal line is exposed through a lower surface of the secondbase and the at least one second signal line is configured to conduct atest current; at least one second ground line in the second base,wherein the at least one second ground line surrounds the at least onesecond signal line and the least one second ground line is exposedthrough a lower surface of the second base; a printed circuit boardbetween the first base and the second base; at least one signal plug inthe printed circuit board to electrically connect the at least one firstsignal line to the at least one second signal line; and at least oneground plug in the printed circuit board to electrically connect the atleast one first ground line to the at least one second ground line. 12.The interposer of claim 11, wherein each of the first base and thesecond base comprises: at least one first via hole vertically formedthrough the first base and the second base, wherein the at least onefirst via hole in the first base is configured to receive the at leastone first signal line and the at least one first via hole in second baseis configured to receive the at least one second signal line; and atleast one second via hole vertically formed through the first base andthe second base, wherein the at least one second via hole in the firstbase is configured to the receive the at least one first ground line andthe at least one second via hole in the second base is configured toreceive the second ground line.
 13. The interposer of claim 12, whereinthe first base includes at least one first protrusion protruding fromthe upper surface of the first base to define the at least one via holein the first base, and at least one second protrusion protruding fromthe upper surface of the first base to define the at least one secondvia hole in the first base, and the second base includes at least onethird protrusion protruding from the lower surface of the second base todefine the at least one first via hole in the second base, and at leastone fourth protrusion protruding from the lower surface of the secondbase to define the at least one second via hole in the second base. 14.The interposer of claim 11, wherein the first base and the second basecomprise a resilient material.
 15. The interposer of claim 11, whereinthe at least one first signal line, the at least one signal plug, andthe at least one second signal line have a coaxial vertical axis, andthe at least one first ground line and the at least one second groundline have a coaxial vertical axis.
 16. The interposer of claim 15,wherein the at least one first signal line and the at least one firstground line are arranged in a concentric circle, and the at least onesecond signal line and the at least one second ground line are arrangedin a concentric circle.
 17. A probe card comprising: a multilayersubstrate having at least one needle configured to contact an object; acoaxial board having at least one coaxial signal cable configured totransmit a test current to the at least one needle, and at least onecoaxial ground cable; and the interposer of claim 2 between themultilayer substrate and the coaxial board, wherein the at least onefirst signal line electrically connects the at least one coaxial cablewith the at least one needle, and the at least one first ground lineelectrically connects to the at least one coaxial ground cable.
 18. Theprobe card of claim 17, wherein the first base comprises: at least onefirst protrusion between the base and the coaxial board and configuredto receive the at least one first signal line; at least one secondprotrusion between the base and the coaxial board and configured toreceive the at least one first ground line; at least one thirdprotrusion between the base and the multilayer substrate and configuredto receive at least one first signal line; at least one fourthprotrusion between the base and the multilayer substrate and configuredto receive the at least one first ground line;
 19. A probe cardcomprising: a multilayer substrate having at least one needle configuredto contact an object; a coaxial board having at least one coaxial signalcable configured to transmit a test current to the at least one needle,and at least one coaxial ground cable; the interposer of claim 11between the multilayer substrate and the coaxial board, wherein thefirst base is under the coaxial board and the second base is above themultilayer substrate and at least one first signal line connects to theat least one coaxial signal cable and the at least one second signalline connects to the at least one needle.
 20. The probe card of claim19, wherein the first base includes at least one first protrusionadjacent to the coaxial board to define the at least one first signalline, and at least one second protrusion adjacent to the coaxial boardto define the at least one first ground line, and the second baseincludes at least one third protrusion adjacent to the multilayersubstrate to define the at least one second signal line, and at leastone fourth protrusion adjacent to the multilayer substrate to define theat least one second ground line.